Bunsen burners



y 23, 1961 H. STELLMACH 2,985,233

BUNSEN BURNERS Filed March 6, 1957 m1!! 711mm ||||||1|| INVENTOR.

flaw? zelljzzacfz BUNSEN BURNERS Hans Stellmach, Remscheid, Germany, assignor to Job. Vaillant, K.G., Remscheid, Germany Filed Mar. 6, 1957, Ser. No. 644,280

Claims priority, application Germany Aug. 3, 1956 3 Claims. (Cl. 158-116) This invention relates to Bunsen burners and is particularly concerned with a Bunsen burner suitable for liquid gas.

As it is well known in the art, in gas apparatus, for instance such as gas water heaters, a plurality of candle shaped Bunsen burners may be positioned in parallel and in series on parallel distributor pipes so as to form a burner unit that is capable completely to cover the cross section of a heating chamber. In order to cover a heating chamber cross section with as small a number of burners as possible, and on the other hand to obtain a heating chamber of low structural height, it is desired to have with such Bunsen burners a flame having a height as low as possible and width as large as possible. Burners with oblong, slotshaped gas outlets are therefore used to fulfill these conditions.

It is also known with Bunsen burners to have several slot-shaped gas outlets supplied with gas from one mixing pipe and to provide spaces between the gas outlet slots so as to provide admission of secondary air to the flames from all sides of the burner. However, conventional type Bunsen burners of this kind necessitate a burner head which is complicated in structure and is com posed of several components.

The invention has therefore for its object to provide a burner head with several slot-shaped gas outlets where satisfactory secondary air supply is ensured, and which is simple in construction and can be conveniently manufactured.

This object of the invention is accomplished by an arrangement wherein the burner head mounted on a mixing tube is formed of a unitary body having a funnelshaped basic form, the top opening of this body being contracted to form a pair of slot-shaped gas outlets, this being achieved by inwardly extending folds of its wall to form re-entrant channels permitting the admission of secondary air.

The burner head body can preferably be made of sheet metal and can be shaped accordingly by non-cutting shaping.

An especially advantageous form of construction conceived according to the invention is obtained if the wall of the burner head is so shaped that two slot type gas outlets of the burner are positioned in parallel and in spaced relationship, separated by air admission channels formed between these gas outlets. Sheet-like flames from the gas outlets, fed by a common mixing tube, are obtained in this manner, whereas perfect combustion is achieved without the necessity of using a complicated multi-part burner head.

The burner head conceived and constructed in accordance with the present invention is advantageously rotatably mounted on the mixing tube and can be locked in two positions which are ofiset by 90 degrees relative to each other. It is then possible, with a plurality of accordingly constructed Bunsen burners, to form a burner unit in which the slot-shaped gas outlets of some of the individual Bunsen burners have a parallel orientation nited States Patent F Patented May 23, 1961 with respect to the distributor pipes on which they are mounted, while others may be arranged to form right angles with their distributor pipes. Thus, burner units can be arranged in various combinations, so that circular, oval or rectangular heating chamber cross sections or other areas to be heated can be most uniformly covered with the burner flames.

The invention is more fully explained in the following detailed description by way of a preferred embodiment of the invention and wherein reference is made to Figs. 1 to 5 of the accompanying drawings.

In the drawings:

Fig. 1 shows in schematic representation a gas water heater equipped with a Bunsen burner unit;

Fig. 2 shows two Bunsen burners in partial section;

Fig. 2a is a detail sectional view showing the arrangement of a mixing tube mounted on a distributor pipe;

Fig. 3 is a portion of a heating chamber cross section with Bunsen burner unit, and

Figs. 4 and 5 show other heating chamber cross sections with exemplary forms of flame surface systems.

In Fig. 1, a continuous flow type gas water heater which is supplied with gas initially in liquid form is shown in schematic representation. A heating chamber 2 closed by a heat exchanger 1 is arranged above a burner unit 4 which is composed of a plurality of Bunsen burners 3.

Each Bunsen burner 3 shown in an enlarged scale in Figs. 2 and 3 consists of a mixing tube 5 and a burner head 6, having slot-shaped gas outlets 7 and 7', which is rotatably mounted in the mixing tube 5, and which will be subject to detailed description hereinbelow. The mixing pipes 5 with the individual burners 3 are mounted on several parallel distributor pipes 18, 18' and 18" above orifices 19, so that primary air can enter the mixing tube 5 from below in the direction of the arrow (see Fig. 2a)., The mixing tubes 5 are provided with an impression 20 acting as a catch, while the rotatable shaft 14 of the burner head 6 has two impressions 21 and 21' offset by with respect to each other. These impressions make it possible for the burner head 6 to be locked in the mixing tube 5 so that either the burner slots 7, 7' have a position in parallel or at right angles to the distributor pipes 18, 18', 18".

The burner head 6 has initially been drawn as a funnelshaped sheet metal part. The wall of the burner head 6 is than so shaped by non-cutting deformation that two slot-shaped gas outlet openings 7, 7 positioned in spaced relationship are formed, so that secondary air admission channels 8, 8' are located between the gas outlets 7, 7'.

These air admission channels 8, 8' are formed by reentrant opposite portions folded into the wall of the funnel-shaped body, the top portions 6, 6" of these reentrant portions contacting each other in the centre of the burner head. The gas outlets 7, 7 are formed by this folding of the funnel wall and by simultaneously compressing these folds vertically to the direction of fold-ing. Additionally, a dome-shaped collecting space 12 for the gas air mixture discharged from the mixing tube 5 is formed below the channels so formed. A sieve cap 5 covers the outlet of the mixing tube 5 and projects into the collecting space 12 and into the spaces 11 positioned laterally thereof and leading to the gas outlet slots.

The gas outlets 7, 7 of the burners are on each side limited by vertical wall parts 9, so that a vertical direction of the gas flowing through the outlets is obtained. Impressed longiutdinal ribs 10, 10' or transverse ribs respectively may be employed to obtain sutficient stifiening of the shaped burner head wall.

A principal requirement is that substantially the same quantity of gas flows out at all points of the slot-shaped gas outlets 7, 7', so that a feather of the flame with uniform height can be produced. 1

In order to accomplish this object, the outlets 7, 7' are narrower at their middle portions, while the widths increase continuously towards the ends of the gas outlets in accordance with the increasing length of the path of flow of the gas-air mixture.

The gas-air mixture formed in the mixing pipe 5 by intimate turbulence at the sieve body 5' flows to the slotshaped gas outlets 7, 7, passing through the spaces 11 and 12 of the burner head 6. These spaces 11 and 12 act as stilling spaces, so that the gas-air mixture is discharged in a uniform flow at the gas outlets 7, 7. If flow cross sections are properly dimensioned, a feather of the flame having uniform height is produced at all points of the slot-shaped openings 7, 7' where uniform admission of secondary air is provided from the outside as well as inside through the channels 8, S. The vertical wall parts 9 prevent the gas-air mixture from emitting in an inclined direction from the slot-shaped outlets 7, 7, thereby obviating an undesirable enlargement of the flame, which otherwise would occur if pressure increases.

With a burner head 6 conceived and designed as described above, a. fiame surface 22 effectively substantially rectangular in shape is produced by each of the burners 3. Figs. 3, 4 and 5 show in which manner various areas or cross sections of heating chambers can be uniformly covered with flame surfaces 22 assigned to the individual burners 3 by orienting some of the burner heads 6 at right angles to other heads.

Invention is claimed as follows:

1. A burner head, for use with supply means of a gas burner, comprising a tubular lower portion adapted for connection with said supply means, and an upper portion formed of a single piece of sheet metal and having outer generally flat walls facing generally in opposite directions and each having its side edges diverging upwardly from the tubular portion, oppositely tucked-in reentrant portions extending from the four diverging edges of the outer walls inwardly toward one another with side walls generally paralled to the outer walls, and

extending substantially as high as the outer walls to form with them generally parallel slot-shaped gas outlets, and

connecting end walls extending upwardly between the reentrant side walls having substantially straight edges adjacent to one another at the top thereof at substantially the level of the first mentioned walls; these tucked-in reentrant portions with said end walls forming channels providing passages for the fiow of secondary air to the vicinity of substantially the entire length of said gas outlets so that the same are exposed to the free flow of secondary air on both sides thereof.

2. A gas burner in accordance with claim 1 wherein the top marignal portions of the burner head defining the gas outlets are substantially vertical whereby gas discharged through said outlets is directed to flow in vertical direction.

3. A gas burner in accordance with claim. 1 wherein the slot-shaped gas outlets of the burner head are narrower at theirmiddle portions than at their ends and are progressively wider from said middle portions to the ends thereof to the extent necessary to distribute gas uniformly over the entire length of said outlets.

References Cited in the file of this patent UNITED STATES PATENTS -wwam 

